A dual-functional curcumin strategy for light scattering mitigation in high-fidelity DLP ceramic 3D printing

Light scattering remains a critical barrier in digital light processing (DLP)-based ceramic additive manufacturing, particularly for achieving high precision, fine resolution, and complex geometries. In this study, we present a novel light scattering mitigation strategy by incorporating a multifunctional reactive additive that combines physical light absorption near 405 nm and chemical free radical scavenging. Curcumin effectively suppresses undesired photopolymerization in non-target regions by neutralizing scattered-light-generated radicals, enabling the fabrication of intricate structures with dimensional fidelity approaching the optical resolution limit (~2.6 pixels). The strategy operates effectively at low concentrations (0.01 wt%) without requiring process parameter tuning, offering a broad process window and high reproducibility. Furthermore, the strategy is generalizable across diverse ceramic systems, including light-colored ceramics (Al₂O₃, ZrO₂, and SiO₂), and dark-colored ceramics (SiC) that are particularly susceptible to scattering. The geometric error of printed SiC components remains below 10% even at high exposure doses of 80 and 100 mJ·cm^-2, effectively addressing the long-standing trade-off between curing depth and lateral resolution. This work provides a simple, scalable, and versatile approach for improving resolution in DLP ceramic printing, advancing the reliable production of fine-scale (<50 µm) ceramic architectures for applications in biomedicine, microelectronics, and precision engineering.